Device for diagnostic examination by ultrasonic oscillations

ABSTRACT

An ultrasonic device for examining the internal parts of the body comprising a plurality of ultrasonic transmitters mounted along a horizontal line on a movable carriage and triggered sequentially. A plurality of receivers is mounted on the carriage along a vertical line that intersects the horizontal line at right angles. The movement of the carriage is synchronized with the deflection of an electron beam in a PPI cathode-ray tube to provide a visual display of the surface contour of the internal body part under investigation.

730F626 SR Michel Joseph Auphan, Neuilly sur Seine, France [56]Referenaes Cited [21] App 637,000 UNITED STATES PATENTS 522 ed g :33}3,332,278 7/1967 Wood et a1. 73/67.7 [731 Assignees U S. Philips Co po aon 3,442,579 5/1969 Fnedberg 73/67.7X New York Primary Examiner-CharlesA. Ruehl i Prwmy r 1966 Attorney-Frank R. Trifari rance 5 60559ABSTRACT: An ultrasonic device for examining the internal pans of thebody comprising a plugalit ofpltrasonic transmitters mounted along ahorizuntal line on a movable carriage [54] DEVICE FOR DIAGNOSTICEXAMINATION BY and triggered sequentially. A plurality of receivers ismounted m 3,577,772 J V" .w'i- 1 1 P v 2/ Uluwu-ouuca 30 M [72]Inventors JeanPerill." 73/675- BourgLaReine; --67.9; 128/2; BIO/9.1;.

Q EI on theafi'iag mangave'nical line that intersects the horizontalline at right angles. The movement of the carriage is i i [521 US. Cl73/67.), synchronized with the deflection of an electron beam in a PF! 5128/2 cathoderay tube to provide a visual display athe surface [51] Int.Cl. G0ln 29/04 contour of the internal body part under investigatiofiTPatented May 4, 1971 3,577,772

INVENTORS JEAN PERILHOU MICHEL J. AUPHAN AGENT l l i DEVICE FORDIAGNOSTIC EXAMINATION BY ULTRASONIC OSCILLATIONS The present inventionrelates to a device for diagnostic examination by means of ultrasonicoscillations. More particularly, the invention relates to a diagnosticapparatus in which the oscillations are employed for recording surfacefor nls, especially for echo observation of irregularly cu rve'dsurfaces for topographical study of internal body parts.

It is known to examine internal body parts by means of ultrasonicoscillations which strike the reflecting surface in a directed, narrowbeam. The required ultrasonic transmitter is displaced along a givenpath and, if necessary, turned about one or more axes. The rectilinearmovement in two directions and the scan of a surface by the transmitteralong a circular path during the oscillation of the transmitter around acentral point, are considered to be necessary to capture the reflectionsfrom curved, reflecting surfaces, while the sound transmitter is movedas closely as possible along the outer surface of the body examined.

In order to avoid apparent reflections and inaccuracies in thetopography due to differences in refractive indices, a liquid layer ofappropriate composition is maintained between the ultrasonic transmitterand the surface of the body.

The mechanical construction of a device suitable for determining thespot of internal body parts in this way is particularly complicated andexpensive.

The invention has for an object to avoid this disadvantage. According tothe invention the ultrasonic transmitter is formed by a plurality ofseparate sources of ultrasonic oscillations arranged in a flat planealong a straight or a curved line and adapted to produce a sequence ofultrasonic waves of short duration in narrow beams directed to the bodyorgan to be examined. In a plane at right angles to the plane of thetransmitters there is arranged a plurality of receivers along a linewhich intersects the line of the transmitters.

One embodiment of the device according to the invention will bedescribed hereinafter with reference to the accompanying drawing whichis a diagrammatic illustration of an ap paratus for carrying out theinvention.

The diagnostic device comprises a guide path I which is supported in amanner not shown and along which a carriage 2 is adapted to bedisplaced. By means of an arm 3 a crossshaped supporting frame 6 isconnected with the carriage 2 for fixing two supports 4 and 5 located inorthogonal planes. The supports 4 and 5 may be straight, but one of themor both of then may be curved to a greater or lesser extent if this isdesired for a particular kind of examination. In the device shown, whichmay be used for the examination of the skull of a patient, the supportsare straight. The guide path I is curved and approximately matches theshape of the head.

- 17 has substantially the shape of a point, which is indicated Alongthe support 4, located in the horizontal plane, a plu- A rality ofultrasonic transmitters 7 are arranged. The transmitters connected withthe support 4 so that their direction of radiation passes towards apoint 8 inside the skull, the position of which point is considered tocontribute to the topography of an internal organ. The lines 9 and 10are an approximate indication of such an organ.

The ultrasonic beam produced by the transmitters 7 propagates in anarrow angle 1 which is indicated on the drawing on an enlarged scale.When the carriage 2 is displaced along the guide path 1 the beams scan alinear region between the limits l1 and 12.

The tr tr s r nitters laresuccessively actuated for a short time@Telectriejiile generator.l3-, which may be formed by known electricpulse circuits in conjunction with a distributor for applying the pulsesproduced ir r sequenc e to the various transmitters."l'he"pulsesequences are repeated during the movement of the ciifriag7with"tfi?supports 4 and 5 along the guide path 1. This movement is controlledby a controlmember 14 which regulates the speed of the carriage 2. Therepetition frequency is chosen in accordance with the desired accuracyof the measuring results of each pulse sequence in dependence upon thedisplacement of the carriage in the course of each pulse sequence.

by the reflecting point 8. The central rays 18 and 19 of a transmittedsound wave and of a sound echo at point 8 connect this point with one ofthe transmitters 7 and one of the receivers 15. The location of thereflecting surface determines which of the receivers 15 will capture thesound wave of one of the transmitters 7 during a series of transmittedsound waves.

In order to provide topographical definition of the point 8, use is madeof the known speed of propagation of ultrasonic waves through livingtissue and the duration of time before a transmitted sound wave isreceived as an echo. This transit time of the ultrasonic wave isdirectly proportional to the sum of the distances along the paths 18 and19 of the central beam, which may be determined by means of thedisplacement of a spot on the screen of a cathode-ray tube 20. In thiscase, the electron beam is controlled in a suitable manner, for example,across the screen of a cathode-ray tube so that the beam is cyclicallydeflected and the spot moves along successive radii. In the presence ofan echo signal a control voltage is applied to the control electrode ofthe cathode ray system so that a spot 21 of greater brightness isproduced. The distance of the spot 21 from the limit 22 of the surfacescanned by the beam is pro portional to the lapse of time between thetransmission and the reception of a sound wave.

Echo signals, captured in order of succession, are reproduced alongdifferent radii on the screen 20 since the control-member 14 controlsnot only the movement of the carriage 2 along the guide path I but alsothe deflection of the electron beam. As a result the direction ofdeflection of the beam varies synchronously with the displacement of thecarriage.

The echo signals of the receivers 15 are applied along separateconductors 23 to a computer 24, whereas the control pulses for thetransmitters 7 are supplied along the conductors 25. A number ofinvariable data, suchas the distances of each of the transmitters 7 fromthe center 0 of the cross-shaped supporting member 6 and of each of thereceivers 15 from said center, can be stored in the computer 24.

The computer therefore serves for determining, at the reception of anecho signals, the length of the path of the sound wave from the relevanttransmitter to the receiver capturing the echo concerned. This is doneby a calculation utilizing the known speed of propagation and themeasured time.

According to the equation:

position of point 8=Il21 v L 2L (a )+(a b The position of point 8 of aninternal organ with respect to the center 0 can be determined from thelength of the path found, in which:

L=the sum of the distances [8 and 19,

a the distance of the relevant transmitter from the center b thedistance of the receiver of the echo signal from the center 0.

This equation can be derived by trigonometrical measurement.

We claim:

1. A device for examining internal body parts by means of ultrasonicwaves comprising, ultrasonic transmitter means mounted for movementalong the surface of the body, said ultrasonic transmitter meanscomprising a plurality of separate transmitters of ultrasonicoscillations arranged in a flat plane along a straight or curved line,control means for triggering said separate transmitters in sequence toproduce sequentially ultrasonic waves of short duration in narrow beamsdirected to the body part to be examined, and a plurality of receiversarranged in a plane at right angles to the plane of the soundtransmitters along a line which intersects the line of the soundtransmitter, said receivers being mounted for movement with saidtransmitters along the surface of the body so as to intercept theultrasonic waves propagating through the body after being reflected fromthe surface of the body part under examination.

2. A device & claimed in claim 1 further comprising, a carriagc membermounted for movement along a given guide path, a crossshaped supportmember mounted on said carriage, and first and second support armsfastened on said cross shaped support members, said transmitters andreceivers being mounted on said first and second support arms,respectively.

3. A device as claimed in claim 2, characterized in that the guide pathhas a curved shape matching the curvature of the surface of the bodyhaving the organ to be examined.

4. A device as claimed in claim 2 further comprising a control memberincluding means for displacing the carriage with the transmitters andreceivers along said guide path, and said control means includes acontrolsystem for repeating the sequential triggering of thetransmitters during the displacement of the carriage.

5. A device as claimed in claim 1, characterized in that the repetitionfrequency of said control means is variable.

6. A device as claimed in claim 1 wherein said control means comprises,an electronic pulse generator, and a pulse distributor selectivelyinterconnecting the output of said pulse generator with said separatetransmitters 7. A device as claimed in claim 6 further comprising, meansfor moving said transmitters and receivers, a cathode ray tube withmeans for radially deflecting the electron beam across the displayscreen, a control member having its input coupled to the output of thepulse generator and a first output for controlling said moving means andthereby the movement of said transmitters and receivers and a secondoutput for controlling the sweep of the cathode ray tube beam insynchronism with the movement of said transmitter and receivers.

8. A device as claimed in claim 6 furthencomprisingcomputer meanscoupled to the outputs of the pulse distributor and the outputs of saidreceivers and including means for determining the distance between apoint on the surface of the W566i? that reflects the ultrasonic energyfrom a transmitter and the intersection point of said line oftransmitters and said line of receivers by analyzing the transit time ofthe ultrasonic energy from a given transmitter to a given receiver.

1. A device for examining internal body parts by means of ultrasonicwaves comprising, ultrasonic transmitter means mounted for movementalong the surface of the body, said ultrasonic transmitter meanscomprising a plurality of separate transmitters of ultrasonicoscillations arranged in a flat plane along a straight or curved line,control means for triggering said separate transmitters in sequence toproduce sequentially ultrasonic waves of short duration in narrow beamsdirected to the body part to be examined, and a plurality of receiversarranged in a plane at right angles to the plane of the soundtransmitters along a line which intersects the line of the soundtransmitter, said receivers being mounted for movement with saidtransmitters along the surface of the body so as to intercept theultrasonic waves propagating through the body after being reflected fromthe surface of the body part under examination.
 2. A device as claimedin claim 1 further comprising, a carriage member mounted for movementalong a given guide path, a cross-shaped support member mounted on saidcarriage, and first and second support arms fastened on saidcross-shaped support members, said transmitters and receivers beingmounted on said first and second support arms, respectively.
 3. A deviceas claimed in claim 2, characterized in that the guide path has a curvedshape matching the curvature of the surface of the body having the organto be examined.
 4. A device as claimed in claim 2 further comprising acontrol member including means for displacing the carriage with thetransmitters and receivers along said guide path, and said control meansincludes a control-system for repeating the sequential triggering of thetransmitters during the displacement of the carriage.
 5. A device asclaimed in claim 1, characterized in that the repetition frequency ofsaid control means is variable.
 6. A device as claimed in claim 1wherein said control means comprises, an electronic pulse generator, anda pulse distributor selectively interconnecting the output of said pulsegenerator with said separate transmitters.
 7. A device as claimed inclaim 6 further comprising, means for moving said transmitters andreceivers, a cathode ray tube with means for radially deflecting theelectron beam across the display screen, a control member having itsinput coupled to the output of the pulse generator and a first outputfor controlling said moving means and thereby the movement of saidtransmitters and receivers and a second output for controlling the sweepof the cathode ray tube beam in synchronism with the movement of saidtransmitter and receivers.
 8. A device as claimed in claim 6 furthercomprising computer means coupled to the outputs of the pulsedistributor and the outputs of said receivers and including means fordetermining the distance between a point on the surface of the internalbody part that reflects the ultrasonic energy from a transmitter and theintersection point of said line of transmitters and said line ofreceivers by analyzing the transit time of the ultrasonic energy from agiven transmitter to a given receiver.